the one that went over the skies of russia is very, very small. only a few feet across it at the most. and 2014 it will still be in outer space even though it's a much, much larger rock. and so it's not going to enter the atmosphere and become a meteor. >> reporter: so this one is not going to hurt us. if someone is not a science geek, why should they care about this? >> well, the asteroid represents one of thousands and thousands of rocks that are orbiting between the earth and mars. they are left over debris from the formation of the planets in the solar system. this one got knocked out of the orbit that would have kept it out there between earth and mars and now orbiting the sun in such a way the orbit crosses the earth's orbit. it's most important thing for us is that it does cross the orbit of the earth and might at some distant point in the future pose a threat to the earth. although today it doesn't. it just raises our interest and our awareness about these objects. >> conrad, thank you very much. if you want to learn more about this astero